1.

| x + 2 | = | 2 - 3x |

xét 2 trường hợp :

+) TH1 :

2 - 3x = x + 2

-3x + x = 2 + 2

2x = 4

x = 4 : 2 = 2

+) TH2 : 

2 - 3x = - ( x + 2 )

2 - 3x = -x - 2

-3x - x = 2 - 2

-4x = 0

x = 0 : ( -4 )

x = 0

bài còn lại tương tự

tìm x,biết:(x^2-3)^2=16

\(\dfrac{3x^6-4x^3}{x^3}-\dfrac{\left(3x+1\right)^2}{3x+1}-\dfrac{3x^7}{x^5}=0\)

\(\Leftrightarrow3x^3-4-3x-1-3x^2=0\)

\(\Leftrightarrow3x^3-3x^2-3x-5=0\)

\(\Leftrightarrow x\simeq1,9506\)

2^3x+1=16

2^3x.2=16

2^3x=8

2^3x=2³

^3x=3

x=1

2^{3x+1 = 16}

2^3x+1 = 2⁴

=> 3x + 1 = 4

=> 3x       = 4 - 1

     3x       =   3

       x       = 3 : 3 

       x       =   1

4.3^5x-2=108

3^5x:3²=27

3^5x=3³.3²

3^5x=3⁵

^5x=5

^x=1

a) \(2x\left(x-3\right)+3\left(x-3\right)=0\)

\(\Leftrightarrow\left(x-3\right)\left(2x+3\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x-3=0\\2x+3=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-\dfrac{3}{2}\end{matrix}\right.\)

b) \(x\left(3x-1\right)-5\left(1-3x\right)=0\)

\(\Leftrightarrow x\left(3x-1\right)+5\left(3x-1\right)=0\)

\(\Leftrightarrow\left(3x-1\right)\left(x+5\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}3x-1=0\\x+5=0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{3}\\x=-5\end{matrix}\right.\)

Ta có:

 \(\frac{-84}{44}< 3x< \frac{108}{9}\)

\(\Rightarrow-1,90909...< 3x< 12\)

\(\Rightarrow x\in2;3\)

Có: \(3x=4y\Leftrightarrow\frac{x}{4}=\frac{y}{3}\)

Đặt \(\frac{x}{4}=\frac{y}{3}=k\Rightarrow\left\{{}\begin{matrix}x=4k\\y=3k\end{matrix}\right.\)

Thay \(x=4k,y=3k\) vào \(x.y=108\), có:

\(4k.3k=108\\ \Leftrightarrow k\in\left\{3;-3\right\}\)

+Khi \(k=3\Rightarrow\left\{{}\begin{matrix}x=3.4=12\\y=3.3=9\end{matrix}\right.\)

+Khi \(k=-3\Rightarrow\left\{{}\begin{matrix}x=-3.4=-12\\y=-3.3=-9\end{matrix}\right.\)

Vậy...

`a)ĐK:(x+1)(2x-6) ne 0`

`<=>(x+1)(x-3) ne 0`

`<=> x ne -1,x ne 3`

`b)C=(3x^2+3x)/((x+1)(2x-6))`

`=(3x(x+1))/((x+1)(2x-6))`

`=(3x)/(2x-6)`

`C=1`

`=>3x=2x-6`

`<=>x=-6(tm)`

Vậy `x=-6`

=>3x+3=2x-3             NHO K DUNG DE UNG HO MIK NHE MOI NGUOI 

=>3x-2x=3+3

=>x=6

3x + 69 : 23 = 2x - 108 : 36

3x + 3 = 2x - 3

3x - 2x = -3 - 3

x = -6

3x + 69 : 23 = 2x - 108 : 36

3x + 3 = 2x - 3

3x - 3x = -3 - 3

x = -6

Vậy x = -6

=))

\(\Leftrightarrow3^x\left(1+3^1\right)=108\\ \Leftrightarrow3^x=\dfrac{108}{4}=27=3^3\\ \Leftrightarrow x=3\)